I first made this Overnight Blueberry French Toast Casserole when I needed an easy, hands-off brunch for a weekend crowd. It’s essentially cubed French or challah bread soaked in a vanilla-cinnamon custard overnight, studded with juicy blueberries, then baked until puffed and golden. If you want a quick browse for related prep tips or serving ideas, check this helpful guide to blueberry French toast casserole variations which inspired a few of my swaps.
Why you’ll love this dish
This casserole hits a lot of kitchen priorities at once: minimal morning work, crowd-friendly portions, and familiar breakfast flavors that feel special. It’s budget-friendly because it uses day-old bread, kid-approved thanks to the sweet custard and berries, and flexible enough to suit dairy-free diets with simple swaps. Make it for a holiday morning, a lazy weekend brunch, or when friends drop by prepare it the night before and the oven does the rest.
Step-by-step overview
You’ll cube stale bread, layer it with blueberries, whisk a vanilla-cinnamon custard, pour that over the bread in a buttered 9×13 pan, and refrigerate so the bread soaks up the custard. In the morning you bake it at 350°F until puffed and set. The process is mostly assembly and patience the overnight soak is what gives the casserole creamy texture throughout.
What you’ll need
- 1 loaf French or challah bread (day-old or slightly stale)
- 4 large eggs
- 2 cups milk (whole milk or a dairy-free alternative)
- 1/2 cup heavy cream (or coconut cream for dairy-free)
- 1/2 cup granulated sugar (or brown sugar, optional)
- 1 teaspoon vanilla extract (verify alcohol-free)
- 1 teaspoon ground cinnamon
- 2 cups fresh blueberries (frozen can work)
- Butter for greasing the 9×13 inch baking dish
Ingredient notes: use slightly stale bread so it soaks evenly; very fresh bread can become gummy. If using frozen blueberries, do not thaw first to prevent the custard from turning purple and soggy.
Step-by-step instructions
- Grease a 9×13 inch baking dish well with butter and set it aside.
- Cut the bread into 1 to 1.5-inch cubes. Spread half of the cubes evenly in the prepared dish. Scatter half of the blueberries over that layer.
- In a medium bowl, whisk together the eggs, milk, heavy cream, sugar, vanilla, and cinnamon until smooth and homogenous.
- Pour half of the custard over the first bread layer. Gently press down so the custard soaks into the cubes.
- Add the remaining bread cubes and the rest of the blueberries on top. Pour the remaining custard over everything and press again so the bread is submerged and moist.
- Cover the dish tightly with plastic wrap or foil and refrigerate overnight, or for at least 6 hours. This resting time lets the custard fully penetrate the bread.
- In the morning, remove the wrap and preheat the oven to 350°F (175°C). Bake the casserole for 45 to 55 minutes, until it is puffed, golden on top, and the center is set (an instant-read thermometer should read about 160°F to 165°F).
- Let it cool for 5 to 10 minutes before slicing and serving. This short rest helps it hold shape when cut.
Best ways to enjoy it
Serve slices warm with a dusting of powdered sugar or a drizzle of maple syrup. Fresh whipped cream or a scoop of vanilla yogurt pairs nicely for added creaminess. For a brunch spread, plate alongside a simple green salad with lemon vinaigrette, or bowls of extra berries and toasted nuts so guests can customize. For a richer finish, a spoonful of lemon curd brightens the berry flavor.
Storage and reheating tips
Store leftover casserole covered in the refrigerator for up to 3 to 4 days. Reheat individual slices in a 350°F oven for 10 to 15 minutes, or microwave a serving for 45 to 90 seconds depending on power. To freeze, wrap cooled slices tightly in plastic wrap and place in a freezer-safe container for up to 2 months. Thaw overnight in the refrigerator and reheat in the oven to restore texture. Always cool to room temperature before covering for the fridge, and discard leftovers kept more than 4 days.
Helpful cooking tips
- Use day-old or slightly stale bread; it absorbs custard without collapsing.
- Cut bread into uniform cubes so the soak and bake are even.
- Press the bread gently into the custard to speed absorption, but don’t mash.
- If you want a crisper top, uncover for the last 10 minutes of baking.
- To prevent a soggy center, ensure your custard-to-bread ratio isn’t too high; the recipe amounts are balanced for 1 loaf.
- For food safety, keep the assembled dish refrigerated while soaking and bake within 24 hours for best texture.
- If you prefer an airier texture, try a variation that uses slightly more beaten eggs and less heavy cream; see this recipe for a fluffier blueberry French toast casserole approach.
Recipe variations
- Citrus-Blueberry: Add 1 teaspoon lemon zest to the custard for a bright lift.
- Nut-Crusted Top: Sprinkle chopped walnuts or pecans mixed with a little brown sugar over the top before baking for crunch.
- Vegan/Dairy-Free: Use coconut cream and a plant-based milk; swap eggs for a commercial egg replacer or a chickpea flour custard for best structure.
- Berry Mix: Replace half the blueberries with raspberries or sliced strawberries for a mixed-berry version.
- Savory-sweet: Reduce sugar slightly and add a pinch of salt; serve with ricotta and honey.
Common questions
How long ahead can I assemble this?
You can assemble and refrigerate the casserole overnight, up to 24 hours. Longer than 24 hours can over-soften the bread and negatively affect texture.
Can I use frozen blueberries?
Yes. Keep them frozen and scatter them on top of the bread without thawing. That reduces bleeding of juice into the custard. Expect a little extra moisture; bake an extra 5 to 10 minutes if needed.
Is there a dairy-free version that still tastes rich?
Yes. Substitute coconut cream for heavy cream and a full-fat plant milk for whole milk. Coconut imparts a subtle flavor that pairs well with blueberries. Use a firm dairy-free egg replacer or a well-tested chickpea flour custard if you need it fully vegan.
How do I know when it’s done?
The top should be golden and puffed and the center should feel set when gently nudged. For accuracy, an instant-read thermometer in the center should read about 160°F to 165°F.
Can I double the recipe for a larger crowd?
Doubling works best by making two separate 9×13 casseroles rather than increasing depth in one very deep pan. That ensures even baking and consistent texture.
Overnight Blueberry French Toast Casserole
Ingredients
Method
-
Grease a 9×13 inch baking dish well with butter and set it aside.
-
Cut the bread into 1 to 1.5-inch cubes. Spread half of the cubes evenly in the prepared dish. Scatter half of the blueberries over that layer.
-
In a medium bowl, whisk together the eggs, milk, heavy cream, sugar, vanilla, and cinnamon until smooth and homogenous.
-
Pour half of the custard over the first bread layer. Gently press down so the custard soaks into the cubes.
-
Add the remaining bread cubes and the rest of the blueberries on top. Pour the remaining custard over everything and press again so the bread is submerged and moist.
-
Cover the dish tightly with plastic wrap or foil and refrigerate overnight, or for at least 6 hours.
-
In the morning, remove the wrap and preheat the oven to 350°F (175°C).
-
Bake the casserole for 45 to 55 minutes, until it is puffed, golden on top, and the center is set (an instant-read thermometer should read about 160°F to 165°F).
-
Let it cool for 5 to 10 minutes before slicing and serving.
Nutrition
Notes
Tried this recipe?
Let us know how it was!
Overnight Blueberry French Toast Casserole
Ingredients
Method
- Grease a 9×13 inch baking dish well with butter and set it aside.
- Cut the bread into 1 to 1.5-inch cubes. Spread half of the cubes evenly in the prepared dish. Scatter half of the blueberries over that layer.
- In a medium bowl, whisk together the eggs, milk, heavy cream, sugar, vanilla, and cinnamon until smooth and homogenous.
- Pour half of the custard over the first bread layer. Gently press down so the custard soaks into the cubes.
- Add the remaining bread cubes and the rest of the blueberries on top. Pour the remaining custard over everything and press again so the bread is submerged and moist.
- Cover the dish tightly with plastic wrap or foil and refrigerate overnight, or for at least 6 hours.
- In the morning, remove the wrap and preheat the oven to 350°F (175°C).
- Bake the casserole for 45 to 55 minutes, until it is puffed, golden on top, and the center is set (an instant-read thermometer should read about 160°F to 165°F).
- Let it cool for 5 to 10 minutes before slicing and serving.
